Dairy system



March 3,1953 H Q HORNEMAN ETAL 2,630,060

DAIRY SYSTEM Original Filed Dec. 6, 1940 @WwW-@@- Patented Mar. 3, 1953UNITED STATES PATENT OFFICE DAIRY SYSTEM poration of Delaware Originalapplication December 6, 1940, Serial No. 368,750. Divided and thisapplication April 12, 1947, Serial No. 741,089

Claims.

The present invention relates to the production of milk fat concentrateand butter. More particularly, this invention relates to theimprovements in a system for producing milk fat concentrate and butter.

Prior processes used in the commercial manufacture of butter are,generally speaking, in essence the same and are commonly known as "batchprocesses. Such batch processes geni erally employ a churn for churningcream having a butterfat content of approximately thirty percent (30%)in the production of butter and buttermilk. With the exception of thepreliminary cream treatments and with the exception of minor mechanicalor apparatus changes, there has not been an important or revolutionarymprovement in methods adapted for the commercial manufacture of butter,for many years.

This application is a division of our parent application Serial No.368,750, filed December 6, 1940, and entitled Butter Process, now PatentNo. 2,423,834.

In the art of manufacturing butter, it has long been recognized that aneed existed for improvements in processes for producing butter. Priorinvestigators have suggested various modifications of such oldprocesses. Such suggested modifications have, however, generally failed.One of such suggested modications proposed the use of a process forproducing butter from a plastic or super-cream, containing in theneighborhood of sixty-five percent (65%) milk fat. That particularmodication of the old processes of manufacturing butter, like unto othermodiiications, included a modification contemplating the use of aconverter or agitating means for the reversal of the phase of the milkfat in the cream, i. e., changing the dispersed phase of the milk fat,which is present in the cream, to a continuous phase. Modifications ofthe mentioned type in the accepted processes for the manufacture ofbuter which call for the reversal of the phase of the milk `fat in ahigh fat cream product have not been found to be satisfactory, and as aresult have not proved successful up to the present time.

It is an object of the present invention to provide an improved processfor producing milk fat concentrate.

It is also an object of the present invention to provide an improvedprocess for producing butter.

It is a further object of the present invention to provide a continuousprocess for the production of butter having improved `qualities andcharacteristics.

It is a still further object of the present invention to providecommercially satisfactory processes for producing milk fat concentrateand butter free from the common objectionable characteristics andaspects associated with butter made `by prior usable buttermanufacturing processes.

Other objects and advantages of the present invention will be moreapparent as the following description is considered.

We `have discovered commercially satisfactory processes for producingmilk fat concentrate and butter having the generally desired physicaland chemical characteristics and aspects. The improved processes, ingeneral, include the steps of introducing cream into a zone or chamberwhere-l in the cream is subjected to sub-atmospheric pressure andwherein the cream is subjected to the direct action of steam while undersuch a reduced pressure, concentration of the milk fat in the creambeing processed by subjection of the cream, While at a temperature abovethe melting point `of the milk fat content thereof, to a centrifugingaction, separation of the concentarted milk fat, which has been thusobtained and in which the fat portion thereof is in the continuousphase, from other constituents of the cream, and thereafter working saidconcentrated milk fat product to produce butter having the desiredphysical and chemical characteristics and aspects. The cream used in theabove process may or may not, as appears desirable, be pretreated,although the use of a high quality, pasteurized cream is generallypreferred.

For a more complete understanding of the nature and scope of theinvention, reference may be made to the following detailed descriptionthereof, to be read in connection with and with reference to theaccompanying drawing, wherein thesingle ligure is a flow sheetdiagrammatically illustrating steps or sequences of operationscontemplated by this invention.

As illustrated in the drawing, cream having a milk fat concentration ofapproximatelyl 30 percent to 40 percent is warmed in a prewarming vat lto a temperature of approximately F. to 110 F. (In the event thatneutralization of the cream to be used in the process is desired, theneutralization may be carried out, for example, in the pre- Warming vatl, in accordance with the general practice commonly followed in thebuttermaking art.) From the vat I, the cream is pumped by pump 2 throughconduit 3 into and through filter 4. Steam under a pressure ofapproximately 90 to pounds per square inch is introduced into theconduit 3 at station 5 from a steam supply line 5'. The mixture of thecream and steam in the conduit 3 raises the temperature of the creamsufliciently so that the cream enters the lter 4 at a temperature ofapproximately 135 F. From the filter 4. cream ows through conduit 6 intoa flash pasteuriVer 7. which may. for example. be of the Well recognizedand commonly known Jensen tyre. Fteam is also introduced into a conduitB at station 8 from the steam supply line The mixture of the iilteredcream with the steam in the conduit raises the temperature of the creamsuiciently so that the cream enters the bottom of the 'casteurizer fromthe conduit 8 at a temperature of approximately 150 F. to 160 F. Thecream under generally accepted one-rating conditions remains in theoasteurizer 'I for a period of time of approximately 10 to 15 seconds,during which period of time the cream beiner pasteuriveri is heated to atemperature of approximately 190 F. to 194 F. Fuch additional heating ofthe cream in the pasteurizer l may be accomplished. for example. by theuse of steam for indirectly heating the cream in the manner common inthe art of the well-known Jensen type of oasteuriver. The pasteurizedcream flows from the pasteuriver 'I through conduit 9 to a supply tankI0, from which, in turn. it flows through conduit I I to a :fone ofsub-atmospheric or reduced pressure for vacuum -steam treatment.

The cream having a temperature of approximately 175 F to 190 F. is drawnthrough the conduit II into the vacuum pasteurizer I2, in which existsthe zone of sub-atmospheric or reduced pressure and which vacuumpasteurirer may. if desired. be of the type described in more detail inthe United Ftates Patent No. 2.022.420. The pressure existing within thevacuum pasteuriver or chamber I2 is of a sub-atmospheric 0r reducednature and preferably is maintained at a reduced pressure ofapproximately to 26 inches of mercury, as a result of which the maximumtemperature within the chamber I2 will be approximately 130 to 135 F.Steam under a pressure of anprovimately 90 pounds rer souare inch isintroduced into the bottom of the vacuum pasteurizer or chamber I2through the steam pipes I3. as illustrated in the drawing. whereby thesteam comes into direct contact with the cream within the chamber I2while the cream is under a reduced or sub-atmospheric pressure. Thedesired and preferred pressures and temperatures are readily maintainedin the chamber I2 by withdrawing vapor or volatile gases containingobjectionable flavoring materials through the passage I4 by means of anyconventional apparatus, such as a vacuum rum (not shown).

The treated or destabilized cream, which has suffered practically no netloss or gain in its moisture content, collects in the lower portion ofthe chamber l2. from which it is drawn by pump I5 and forced. throughconduit I6 to the centrifuging separator Il. The cream within theseparator Il is in general terminology of a temperature of approximately125 F., and in each instance should be at a temperature at least abovethe melting` point of the various types of milk fats present in thecream being separated.

In the separator il substantially all of the milk fat is separated fromthe proteins, skim milk, etc., and is discharged therefrom in a mixturein which the milk fat portion thereof is in the continuous phase and ina liquid form. The mixture containing the milk fat is expelled from theseparator at the station I0 and contains approximately 80 percent to 98p-ercent milk fat, depend- 4 ing upon the extent of the above-mentionedcentrifueing action. vThe major portion of such milk fat is in thecontinuous phase, and is next passed from station I8 through conduit I9to the vat 20. From the vat 20 the milk fat product, with the milk fatstill in a liquid state and in the continuous phase, is pumped by pump2| through the conduits 22 and 23 tothe mixing chamber 24. A controlledaqueous solution of salt, starter flavors, etc., may be pumped at apredetermined rate from the vat 25 by the pump 26 through the conduits21 and 23 into the mixing chamber 24, wherein such aqueous solution maythen be mixed with the fat product supplied to the chamber 24 from thevat 20. The resulting mixture, containing at least 80 percent milk fat,is then conducted from the mixing chamber 24 through conduit 28 to acooling and stabilizing unit 29, wherein the temperature of themixtureis reduced to a temperature of approximately 40 F. to 60 Thecooled and stabilized 'mixture is conducted from thel cooler andstabilizer 29 through the conduit 30 into the tempering unit 3l, whereinthe desired texture is imparted or developed in the butter thusproduced. The tempered product is forced from the tempering unit 3| andconducted through the conduit 32 to a suitable packaging machine (notshown). y

It will be understood that the above representative detailed descriptionof the preferred method of practicing the improved process is merelyillustrative and that the present invention is not limited thereto. Thepre-treatments, including filtering and pasteurizing the cream, may bemodified or eliminated in whole or in part, as desired.

Pasteurization of the cream, for example, may be performed entirely bymixing steam and cream. The working ofthe milk fat mixture after it isdischarged from the separator, including mixing the mixture with waterand with salt or with brine if salted butter is desired, etc., as wellas the cooling and tempering, commonly referred to in the art ofbuttermaking as aging, may also be Y modied if desired. Optimumconditions which to in the preceding detailed description of 'theimproved process, of necessity represent one set of preferred conditionsfor the practice of the improved process. temperatures and pressures,however, may also be modied as desired and necessary and optimumconditions, including the necessary time of treatment within the vacuumpasteurizer (e. g. 5 to 30 minutes), should be varied on the basis ofthe particular type of cream undergoing treatment.

The change in the cream during the vacuumsteam treatment is n-ot fullyunderstood. Our investigations indicate that subjecting the cream tosub-atmospheric pressure produced an expansion of the cream, and thatthe action of the .Y

steam (e. g. steam under a high pressure of to pounds per square inchimmediately ahead of the steam nozzle), cominginto direct contact-I'with the cream which is in the expanded state.'

The mentioned illustrativemodies or destabllizes the milk fat globulesso that they separate into the continuous phase when later subjected tothe centrifuging action in the separator. Our investigations alsoindicate that the best results are obtained when the cream entering thezone of sub-atmospheric pressure is preheated to a temperature greaterthan the temperature of saturated steam at a reduced or sub-atmosphericpressure within the mentioned zone. The fact that the fat is obtained inthe continuous phase indicates that the complex protein-fat-hull ormembrane surrounding the milk fat globule is modied physically orchemically or both by the combined vacuum and steam treatment in chamberI2. It will be understood, however, that the present invention is notlimited by theoretical explanations.

The addition of a controlled amount of water to the concentrated milkfat enables the securing of a more uniform or iiner dispersion of waterin a water-in-fat emulsion, resulting in an improved texture in thebutter made from such emulsion` The amount of water added varies withthe percentage of milk iat in the concentrated milk fat emulsion, whichconcentrated milk fat emulsion preferably contains 85 percent to 95percent fat. The amount of water thus added to the milk fat emulsion iscontrolled so that the final butter product contains at least 80 percentmilk fat.

The aspect of the present invention pertaining to the fine dispersion ofwater or brine in the milk fat emulsion and the low protein content ofthe emulsion, as well as the removal of substantially all of theoriginal water and water soluble materials from the milk fat which is tobe used for the manufacture of butter, enables the advantageous use ofthe invention in the production of a stable butter. A substantialproportion of nitrogenous material-one of the bacterial foods inbutter-is separated from the milk fat in the centrifugal separator.

As previously mentioned, the raw milk or cream as contemplated by thisinvention contains only approximately 35 percent milk fat. Theadvantages obtained by replacing the original non-fat materials of thecream with controlled water starter mixtures free from undesiredcontamination will be obvious to those skilled in the art. An additionaladvantage of the present invention resides in the elimination ofchurning commonly carried out today, for the most part, inbacteria-contaminated wooden churns.

It would be obvious to those skilled in the art that the milk fatconcentrate of the present invention is particularly adaptable for useas an intermediate in the preparation or manufacture of butter, in whichthe quality and composition of the concentrate may be accuratelycontrolled.

It will also be obvious to those skilled in the art that the mentionedmilk fat concentrate is also adaptable for use in the manufacture ofcheese, ice cream, frozen desserts, confections, baked goods and thelike.

It will be understood that the present invention is not limited to theillustrative process herein described. All modications coming within thescope of the present invention are intended to be covered in theappended claims.

In the specications and claims. the term "starter refers to startercultures. Such cultures are Well known in the art of buttermaking andserve as means for avoring the manufactured butter. In thespecifications and claims, the term cream is used with the thought thatit is to be given the ordinary or conventional meaning and is used toidentify a product in which the milk iat is in the dispersed phase, i.e., the milk fat dispersed as an emulsion in a continuous phase ofnon-fat milk liquids. Cream products differ materially from theconcentrated iat or fat concentrate of the present invention, in whichfat concentrate the milk fat is present in the continuous phase.

The invention is hereby claimed as follows:

l. A system for carrying out a physical chemical reaction, comprising avat, an agitating type heater, a separator closely coupled to saidheater, a mixing chamber, a cooling and stabilizing unit, a temperingunit, conduit means connecting all in series in the order mentioned, andpump means associated with said conduit means for circulation of theproduct being processed through said series-connected devices in theorder mentioned.

2. Means for converting a butter-forming mixture of liquid milk fat inthe continuous phase and water which may include salt and avor starterin desired amounts into butter, which comprises, in combination,chilling and stabilizing means wherein the liquid butter-forming mixturemay be chilled in a continuous operation and stabilized, a temperingunit connected to said chilling and stabilizing means and adapted toimpart a true butter texture to the chilled butter in a continuousoperation, and circulating means for circulating the mixture throughsaid connected chilling and stabilizing means and said tempering unit.

3. A coordinated apparatus for the continuous production of butter,comprising, in combination, means for destabilizing a dairy productcontaining milk fat in the dispersed phase, separating means closelycoupled to said destabilizing means for separating a substantial portionof the milk fat from the destabilized dairy product to produce aseparation fraction having a high milk fat concentration in thecontinuous phase, cooling and stabilizing means for cooling andconcurrently stabilizing the separated portion of the dairy productcontaining the high milk fat concentration to produce a plastic butterin which at least a substantial portion of the milk fat is crystallized,and connecting and circulating means for connecting all in series in theorder mentioned and for causing the circulation of the product beingprocessed therethrough.

4. A coordinated apparatus for the continuous productionof milk fatconcentrate comprising in combination means for destabilizing a dairyproduct containing milk fat in the dispersed phase, separating means forseparating a substantial portion of the milk fat from the destabilizeddairy product to produce a separation fraction having a high milk fatconcentration in the continuous phase, conduit means therebetweenwhereby destabilized dairy product may pass from said destabilizingmeans to said separating means, and means for causing the circulation ofthe product being processed therethrough.

5. A system for carrying out a physical, chemical reaction, comprising avat, an agitating type heater, a separator closely coupled to saidheater, a mixing chamber, a cooling and stabilizing unit, a temperingunit, conduit means connecting all in series in the order mentioned, andpump means associated with said conduit means for circulation of theproduct being processed through said series-connected devices in theorder mentioned, said series-connected system being provided withBERNARD W. HAMMER.

REFERENCES CITED The following references are of record in the lo fileof this patent:

' UNITED STATES PATENTS Name Date Hewitt Apr. 20, 1897 Seymour Nov. 7,1933 Gerstenberg Aug. 11, 1936

